If the miners are extracting information from a shared pool of transactions can the same transaction be in multiple blocks, and therefore be in the Blockchain multiple times?
No. The transaction goes only in one block.
The number os confirmations is the number of mined blocks after that transaction has been added to a block.
I made a brief summary here
https://bitcointalk.org/index.php?topic=3317586.msg34646752#msg34646752In this explanation it seems it is saying one transaction = one block. There are thousands of transactions per block however.